Refrigeration



May 29, 1945.

0. B. SUTTON REFRIGERATION 2 Sheets-Sheet 1 Filed Aug. 23, 1940 Alma mp m

INVENTOR 0113 B. Sailor:

ATTO R N EY 0. B. SUTTON REFRIGERATION May 29, 1945.

Filed Aug. 25, 1940 2 Sheets-Sheet 2 '\JVE.I\. k. R 1 011's .5. Six/Z012 BY WSAFHIRNEY Patented May 29. 1945 2,311,051 harmonization Otis B. Sutton, North Canton. Ohio. aasignor to The Hoover Column-North Canton, Ohio Application August 2:. mo, Serial n ssasos 21 Claims. (01. 02-5) This application relates to the art of refrigeration and more particularly to a novel absorption refrigerating mechanism so constructed and arranged that the refrigerating effect may be caused to occur selectively in a high temperature refrigerating zone or in a low temperature refrigerating zone.

provide a refrigerating. system of the three-fluid It is a further object of the present invention to tubular air-cooled absorber A, an air-cooled rec- V tiner R, a solution reservoir 8, a liquid heat exchanger L, a. gas heat exchanger 6, a fast-freezing evaporator E, a high temperature evaporator o E, a tubular air-cooled condenser C, and a gas circulating fan 1' which may be driven by a suitable electrical motor M.

The above described refrigerating system willbe charged with a suitable refrigerant, such as absorption type in which the liquid refrigerant 1 l" ammonia, a suitable absorbent therefor, such as and inert gas are directed selectively into a selected one of a plurality of evaporating zones in" order system are operative to direct the refrigerant and inert gas into a selected area of the. evap rating zone and in which the said movable means are energized hyamechanism externallyofthe system having no moving'parts through theiluidcontainingwallsthereof. j

Other objects and advantagesof-theinvention willbecomeappaientasthedescriptionproceeds when taken in connection with the accompanyinEdrawings,inwhich- Flgurelisapartialsectionalelevationalview ofarefrigeratin macluneembodyingthepresent 4 invention, and

-l"lgure2isaperspectiveviewoftheevaporating mechanism and control construction drawn toanenlargedscale.

Referring now to the drawinss'in detail and .flrstto'Figurel thereof. thereisillustrated'arefl'lserator cabinet it which includes an insulated food storage'compartment ii which underlies an insulatedfreesing comparilnent if. The'com-' an insupartments ii and]! areseparatedby lated partition". Aninsulateddooril provides accesstotbeeompartmentsli and-ltandasuitable inner door ll provides access to the compertinent i2 aloneand prevents loss of-eold air therefrom when thedoor it is opened merely to provideaccesstothe'compartmentll. Amoebanisment il underliesandextendsupwardlyalongtherearwalloftheh uponasuitablebasememberll.

4! suitable Iefrlgeraflng atedwitht'wcabinetstructure. Thismechanism isaaaoci water, and an inert pressure u lizing medium preferably a dense gas like nitrogen.

The boiler and absorber are connected to form a solution circuit as follows: Weak solution is conl5 veyed from the boiler to the upper portion of the absorber by way of conduit 2., liquid heat exchanger L, conduit 2 i, solution reservoir 5, finned air-cooled conduit 22, and gas lift pump conduit 23. The reservoir is vented to the suction conduit .24 of the fan by means ofv a conduit 2|.

Pumping gas is supplied to the gas lift pump conduit 23 below the liquid level normally therein contained by means of a conduit 2| which receives gas from the discharge conduit 21 of the circulating fan. The lean solution traverses the absorber by gravity in counterilow relationship to amixtureofpressureequalisingmediumandrefrigerant vapor flowing upwardly therethrough. The lean solution absorbs refrigerant vapor amthe mixture forming rich solution and the resulting heat'of absorption is reiecied to cooling airnowingoverthennsontheexterlorwallsof the absorber tubes. The resulting rich solutionis thenremrnedtotheanalyrerbywayofthecons5 duit "(liquid heat exchanger L, and the conduit.

Theboilerisheatedbymeansofasuitable heatinaelementliwhiehisillustratedasagas .',burner' including a suitable flame failure safety 40 cut-oflmechanism. nielissuppliedtotheb nner Hbywayofaconduitliwhichindudesthasoh noid control valve V. A suitable by-passlt is providedaroundthevalvevinordertomaintain apilotorignitingiiameupontheburnerll. The

valveviseontrolledinamannertobedescribed hereinafter. Waste products of combustion are of the vertically extendingportionof the mechanismccmpartment l1. Theilue "terminates adiacent the top wall of the cabinet construction though itis shown broken at thelbottom portion thereof in order to facilitate illustration.

The absorber. gas heat exchanger, circulating "fan and evaporator are connected in an inert ii audit. Thecabinet gas circuit as follows: The lean gas formed in the absorber flows through the conduit 24 to the circulating fan P where his placed imder pressure and discharges through the conduit 21 into'the comprises a boiler B, an analyser D, a 'inelined .outer path of the gas heat exchanger 0. After traversing the gas heat exchanger G, the lean gas is conveyed from the upper portion thereof by a conduit 36 into a gas flow control chamber 38 (see Figure 2).

The gas flow control chamber 38 communicates with the evaporators E and E by means of the gas supply conduits 39 and 40, respectively. After traversing one or the other of the evaporators E or E the inert gas is supplied to the inner path of the gas heat exchanger by means of the conduits 4| or 42, respectively. Referring back to Figure 1, after traversing the gas heat exchanger the rich inert gas is conveyed from .the bottom portion of the gas heat exchanger G to the lower portion of the absorber A by way of the conduit 44 through which it flows in the manner heretofore described, thus completing the inert gas circuit.

The refrigerant vapor produced in the boiler B flows upwardly through the analyzer D in counterfiow to strong solution flowing downwardly therethrough. The resulting purified vapor is conveyed from the upper portion of the analyzer to the upper portion of the air-cooled condenser C by means of the conduit 50 which includes the air-cooled rectifier R. The refrigerant vapor is liquified in the condenser C and discharges from the bottom portion thereof through a downwardly extending U-shaped conduit into a refrigerant flow control chamber 52. The condenser side of the U-shaped conduit 5| is vented by means of aconduit 53 into the inner pass of the gas heat exchanger G.

Referring now to Figure 2, the refrigerant fiow control chamber 52 is .connected to the .evaporators E and E by means of the conduits 55 and 56, respectively.

The arrangement of the absorber with respect to the lower portion of the compartment I1 is such that cooling air may flow into the bottom and rear portions of the chamber l'l, flow over the absorber upwardly through the chamber I! along the rear wall of the storage chambers, over the rectifier and condenser and then discharges through the top of the cabinet construction. This cooling air serves to carry off the heat rejection by the absorber, rectifier and condenser. The boiler, as is illustrated, is positioned in the bottom central portion of the, chamber l1 and the circulating fan F and motor M are positioned in the bottom portion of the vertically extending part of the chamber II. The gas heat exchanger G is partially embedded in the rear insulated wall of the compartments II and I2 and is provided with a suitable insulating blanket 51 on the outside thereof. The rear wall of the compartments II and I2 is provided with an opening. 58 which extends above and below the partition 13. A suitable insulated closure member 59 is provided to fit into the opening 58 to seal the same inconjunction with a sealing gasket 60. The upper portion of the gas heat exchanger G, the refrigerant fiow control chamber 52, and the inert gas -flow control chamber 38 are housed within the insulated portion of theclosure member 59. The

division panel l3 may be mounted upon the closure element 59 or may be mounted upon the cabinet construction proper, as desired. However, as illustrated, the division panel I3 is mounted upon the cabinet construction. With this arrangement the refrigerating mechanism may be slid into the cabinet from the rear, thus positioning the evaporators E and E above and below the partition I3, respectively, closing the opening 58 and positioning the absorber-boiler assembly in the bottom portion of the compartment I! and positioning the condenser-rectifier in the vertically extending portion thereof.

The evaporators E and E are each designed to be of the type in which the inert gas will travel therethrough at a velocity sufficientto sweep the evaporating liquid refrigerant through the evaporator by the frictional drag of the inert gas stream flowing thereby. This arrangement renders the evaporator independent of inaccurate manufacture and non-leveling installation of the apparatus. It also assures positive propulsion of the liquid refrigerant and effective distribution thereof to all operative or effective portions of the evporating conduit. This subject matter per se forms the subject matter of the co-pending application of Curtis C. Coons and William H. Kitto, Serial No. 220,189, filed July 20th, 1938, now Patent No. 2,328,196, dated August 31, 1943.

As illustrated, the evaporators E and E are each in the form of a substantially horizontal coiled conduit connected between the conduits 39 and 4| and the conduits 40 and 42, respectively. This is the preferred form of evaporator but other known forms may be utilized, if desired.

The evaporator E is positioned in the extreme upper portion of the chamber ll just under the partition l3 and is provided with suitable aircooling fins 63. The evaporator E extends horizontally in the lower portion of the compartment l2 but far enough above the panel I3 to provide a storage space therebetwen. A suitable shelf, if desired, may be positioned over the evaporator E in order to receive'ice-freezing trays or the like.

Referring now to Figure 2, the control mechanism will be described. As is illustrated in Figure 2, the evaporator gas supply conduits 39 and 40 open into the top and bottom respectively of the flow control chamber 38 and the gas supply conduit ,36 opens into the side thereof. A valve element. 10 adapted to close communication between the chamber 38 and either of the conduits 39 and 40 is mounted within the chamber 38. The valve member 10 may be made of magnetic material or it may be made of non-magnetic material provided with magnetic inserts so that it may be operated by the magnetic field of the winding H. In Figure 2 the winding II is shown diagrammatically above the chamber 38 but it will be understood that the same is wrapped around the top portion-thereof as is indicated in Figure 1. When the winding 'H is de-energized the valve element 10 drops under its own weight and seals the conduit 40 from communication with the interior of the chamber 38 whereby the inert gas flowing through the conduit 36 flows in its entirety into the evaporator E through the conduit 39. Conversely, when the winding H is energized the valve element 10 is lifted by the magnetic attraction thereof and seals communication between the chamber 38 and the conduit 39 whereby all inert gas supplied to the conduit 36 flows into the evaporator E through the conduit The liquid refrigerant control chamber 52 communicates at its bottom portion with the supply conduit 56 of the evaporator The refrigerant supply conduit 5| opens into one side of the chamber 52 and the supply conduit 55 of the evaporator E opens into the opposite side thereof. A valve element 13 is mounted within the chamber 52 and may be constructed of magnetic material or may be made of non-magnetic material provided with magnetic inserts. The lower end of the element 13 as illustrated is provided with a valve-seat 19 "designed to-drop into and to seal the upper end of the'conduit 99. A suitable solenoid I is wrapped about the upper.

portion of the chamber 52 as'is illustrated in Figure 1.; When the solenoid 19 is deenergized the valve element 19 drops of its own weight andthe .valve seat 14 thereof seats in I the conduit 59, thereby. breaking communications between the conduit 59 and the chamber 92.

tion thereof lifts thevalve element 19 from its connects to a conductor 99. The conductor 99- is connected directly to'the stationary contact 99 a of aswitching mechanism as. The conductor the conduit 59 connected to'the stationary contact I99 by means of a conductor III.

Referring now to Figure 1, the switching mechanism 99 is shown as being positioned in the top frontportion of the compartment I2 and a suitable knob I29 is provided for adjusting the cam 99; The switch 92 may also be included in this assembly if desired. with this arrangement the thermostat 99 will respond to the temperature of the air within the compartment I2; however,

, it is within the purview of the invention to have is. also connected to one end of each of the solenoid windings II and 15 by means of a conductor 89 and is connected to a stationary contact 81 of a second thermostatic switching mechanism .99 by means of a conductor 89.

The thermostatic switch 95 comprises a bimetallic element 99 mounted upon a fixed supcam 99 is mounted to bear upon the lower face of the thermostatic mechanism 99 in order to resist downward, movement thereof thereby to vary the temperature at which the circuit is madebetween the contacts 99 and 95. The cam is also provided with a projecting nose 91 which will'force and hold the contact bar 92 in contact ture of the evaporator E, if desired. 7

The switching mechanism 88 is mounted within the top'rear portion of the compartment II and the thermostat 99 therein responds to .temperature of the air such compartment,

the thermostat respond directly to the temperabut it is within the purview of the invention so to arrange the'switching mechanism99 that the thermostat 99 responds directly to the temperature of the evaporator E The operation of the control mechanism is as follows: Assume that the apparatus has not been operating and that both of the compartments II and I2 are above the control temperature there- Under these conditions the bimetallic elements 99 and 99 will have flexed downwardly into contact with the stationary contacts 89, 95, 81, I99, I95 and I99. Under these conditions the solenoids 1| and 15 are de-energized by reason of the open circuit between the stationary contacts 93 and Y99. Therefore, the valve mechanisms 19 and 19 will be in the position shown in Figure 2 and all liquid refrigerant and inert gas will be supplied to the-evaporator E through the conduits 59 and 39; respectively, and no liquid refrigerant or inert gas will be supplied to the evaporator E. The valve V and motor M will be energized through the following circuit: 8I V,

with the" stationary contacts 99 and 99 regardless of the temperature when the nose 91 is brought to bear upon the vbi-metallic element 99..

A switching mechanism 88 comprises a thermostatic bi-metallicelement 99 which is mounted upona fixed support I99. At its free end the iii-metallic element 99 carries an insulating plate "I which in turn carries a pair of-contact bars "I92 and I99 which are insulated and spaced from each other. The contact bar I92 is designed to contact a pair of stationary contacts 91 and I99 andthe contact bar I99 is designed to complete the circuit between a pair of stationary contacts, I95 and I99. The arrangement is such that both circuits are made and broken simultaneously.' I

The stationary contact 99 is connected to one' of a conductor I I9; The'motorM is in turn con nected to the solenoid valve V by means of a conductor H9 and the solenoid valve V is then H9, M, H9, H2, I99, I92, 91, 99, 99,82 and 89. The apparatus will continue operating in this manner until the temperature within the compartment I2 reaches the value for which the apparatus is set whereupon the thermostat 99 will flex upwardly opening the circuit between the elements 99 and' 95 and closing the circuit between the contacts 99 and 99. The position of the thermostatic element 99 will be unchanged as no refrigeration has been produced within the compartment II by the evaporator E. The solenoid coils 1.9 and 1| will now be energized through the following circuit:

99, 92, 99, 99, I5 and 'H, 9,99, 92, 99, Ill, I95,

:1, as, a, a: and so. This mode of operation, will continue until the refrigerating means in the compartment. have been satisfied in which event the thermostatic element 99 will respondwill raise the contacts I92 and I99, thus breaking the circuit between the contacts 91 and I99 and I the contacts I99 and I99, respectively.-

The above assumesthat the refrigerating conditions within the compartment I2 remain satisfactory during the period when the refrigerating needs of the compartment II were beingmet. However, if the temperature within the compartment I2 should rise beyond the control point :before'the'refriserating needs of the compartto the line 9|. The line 9'I is also '75 ment are satisfied, the thermostatic element 90 would flex downwardl into the position described in connection with the first series of operation, thus de-energizing the coils II and I5 and re-energizing the solenoid valve V and motor M through the stationary contacts 84 and 95.

Should the refrigerating needs of the compartment ll be met, the thermostatic element 98 will flex upwardl as viewed in Figure 2, and energization of the motor M and valve V will then be through the following circuit: 8|, V, I ll, M,

H3, 2,95, 92, 84, 83, 82 and 80'.

Consequently, it may be seen from this that the apparatus is arranged to supply the refrigerating demands of either compartment but that the needs of the fast-freezing compartment take precedence over those of the storage compartment. However, the cam 96 is provided to reverse this arrangement to give precedence to the needs of the storagecompartment if so desired and to vary the control point in compartment l2 without affecting the control point in compart ment I l. I

, Though the apparatus has been disclosed with a particular order of precedence, it is within the scope of the invention to reverse the relative positions of the thermostatic switch constructions 85 and 88 in order to give preference to the food storage compartment if that arrangement should be desired.

The present invention thus provides an arrangement in which low temperature refrigeration may be provided in a low temperature compartment for the purpose of freezing ice and storing foodstuffs requiring low temperature refrigeration, while higher temperature and consequently higher humidity refrigeration may be produced in another compartment for normal foodstuffs storage preservation. This is accomplished by totally diverting the flow of both liquid refrigerant and inert gas from one evaporating zone to theother, thereby rendering one or the other evaporating zone totally inactive. The control mechanism is so constructed and arranged to give precedence to a selected one of the refrigerating zones and means are provided for reversing this order of precedence temporarily in order to meet extraordinary demands. unusual needs, or the like. 7

While the invention has been illustrated and described herein in considerable detail, various changes may be made in the arrangement, construction and proportion of parts without departing from 'the spirit of the invention or the scope of the appended claims.

I claim: I

1. Hermetically sealed absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit 4 including said absorber and a pair of evaporators,

means for liquefying refrigerant vapor produced in said boiler, means for directing the inert gas -and liquefied refrigerant into one only of said evaporators, and magnetic means positioned exteriorly of the fluid confining walls of said apparatus foroperating said directing means.

selected one of said evaporators, magnetic means positioned exteriorly of the fluid confining walls of the apparatus for operating said flow control means by the force of a magnetic field passing through said fluid confining walls and refrigeration demand responsive means for controlling the operation of both of said flow control means.

3. Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including said absorber and a pair of evaporators, means for liquefying refrigerant vapor produced in said boiler, flow control means in said inert gas circuit arranged to restrict the flow of inert gas to a selected one of said evaporators, means including flow control means arranged to convey refrigerant liquid from said liquefying means to said selected one of said evaporators, and refrigeration demand responsive means for controlling the operation of both of said flow control means, said refrigeration demand responsive means being arranged to meet the refrigerating needs of one of said evaporators in preference to the other thereof.

4. Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including said absorber and a pair of evaporators, means for liquefying refrigerant; vapor produced in said boiler, flow control means in said inert gas circuit arranged to restrict the fiow of inert gas to a selected one of said evaporators, means including flow control means arranged to convey refrigerant liquid from said liquefying means to said selected one of saidevaporators, refrigeration demand responsive means for controlling the operation of both of said flow control means, said 2. Absorption refrigerating apparatus comprislected one of said evaporators, means including flow control means arranged to convey refrigerant liquid from said liquefying means to said refrigeration demand responsive means being arranged to meet the refrigerating 'needsof one of said evaporators in preference to the other thereof, and manually operable means for reversing the order of said preference.

5. Absorption refrigerating apparatus comprising. a solution circuit including a boiler and an absorber, an inert gas circuit including said absorber and a pair of evaporators, means for liq uefying refrigerant vapor produced in said boiler, flow control means in said inert gas circuit arranged to restrict the flow of inert gas to a selected one of said evaporators, means including flow control means arranged to convey refrigerant liquid from said liquefying means to said selected one of said evaporators, refrigeration demand responsive means for controlling the operation of both of said flow control means, said refrigeration demand responsive means being arranged to meet the refrigerating needs of one of said evaporators in preference to the other thereof, and manually operable means for operating said'flow control means to a particular operable position independently of refrigeration demand.

6. Refrigerating apparatus including a cabinet construction having high and low temperature refrigerating compartments insulated from each other, an evaporator having a part in said high temperature and a part in said low temperature compartment, means for circulating an inert gas through a circuit including each of said evaporator parts, flow control means for preventing inert gas flow through one of saidte m parts, a source of refrigerant liquid, -fiow control means for directing liquid refrigerant from said source only into the evaporator partthrough which inert gas is flowing and temperature re-" aa'mos sponsive means for governing the, operation of both of said flow control means.

7. Absorption refrigerating apparatus compris- 7 ing a solution circuit including a boiler and an absorber, an inert gas circuit'including said absorber and a pair of evaporators, means for liquefying refrigerant vapor produced in said boiler,

means for heating said boiler, means in said inert gas circuit for circulating the inert gas, flow control means for directing liquid refrigerant from said liquefying means into a selected one of said evaporators and for preventing fiow of inert gas through the other of said evaporators, thermostatic means responsive to a thermal condition produced by one of said evaporators arranged in one position to operate said fiow control means in a predetermined manner and in another position to energize saidheating means and said circulating means, and thermostatic means responsive to of liquid refrigerant including a heated part,-

means for heating said heated part, means for circulating an inert gas through a circuit including said evaporators and a control device for restricting inert gas fiow to a selected one of said evaporators, means for conducting liquid refrigerant from said source of liquid refrigerant to said evaporators including a control device for restricting the flow of liquid refrigerant to said selected one of said evaporators, control mechanism arranged to control said heating means, said circulating means and said flow control devices to limit production of the refrigerating effect to a selected one of said evaporators at any one time, and means for altering the temperature maintained by one of said evaporators without altering the temperature maintained by another of said evaporators.

9. In an absorption refrigerating mechanism, a source of refrigerant liquid including a heated part, means for heating said heated part, a first evaporaton, a second evaporator, an inert gasv circulating means, means for directing the flow of inert gas from said circulating means to a selected evaporator, means for directing refrigerant liquid from said source of refrigerant 4 liquid to said selected evaporator, a first thermostatic means responsive to a thermal condition produced by said first evaporator, and a second thermostatic means responsive to a thermal condition produced bysaid secondevaporator, said first thermostatic means being arranged to condition said flow din rccting means for operation under the control of said second thermostatic means to direct refrigerant liquid 'andinert gas, into said second evaporator when there is no demand for refrigeration by said first evaporator and to condition said flow g means to supply refrigerant liquid and inert gas to said first evaporator and to energize said heating means and said circulating means to produce refrigeration in said first evaporatorin response to a demand therefor.

10. In-an absorption refrigerating mechanism, a source of refrigerant liquid including a. heated part, means for heating said heated part, a first evaporator, a secondevaporator, an inert gas circulating means, means for directing the fiow of inert gas from said circulating means to a se- I 5 lected evaporator, means for directing refrigerant liquid from said source of refrigerant liquid to said selected evaporator, a first thermostatic means responsive to a thermal condition produced by said first evaporator, and a second thermostatic means responsive to a thermal condition produced-by said second evaporator, said first thermostatic means being arranged to conditionsaid flow directing means for operation under the control of said second thermostatic means to direct refrigerant liquid and inert gas into said second evaporator when there is no demand for refrigeration by said first evaporator and to condition said flow directing means to supply refrigerant liquid and inert gas to said first evaporator and to energize said heating means and said circulating means to produce refrigeration in said first evaporator in response to a demand therefor, saidsecond thermostatic means being arranged to energize said heating means and said inert gas circulating means in response to a demad for refrigeration by said second evaporator.

, 11., In an absorption refrigerating mechanism,

a source of refrigerant liquid including a heated part, means for heating said heated part, a first evaporator, a second evaporator, an inert gas circulating means, flow directing means for directingthe fiow of inert gas from said circulating means to a selected evaporator, fiow directing means for directing refrigerant liquid from said source of refrigerant liquid to said selected evaporator, a first thermostatic means responsive to a thermal condition produced by said first evaporator, a second thermostatic means responsive to a thermal condition produced by said second evaporator, said first thermostatic means being arranged to condition both of said flow directing means for operation under the control of said second thermostatic means to direct refrigerant liquid and inert gas into said second evaporator when there is no demand for refrigeration by said first evaporator and to condition both of said fiow directing means to supply refrigerant liquid and inert gas to said first evaporator and to energize said heating means and said circulating means to produce refrigeration in said first evaporator in response to a demand therefor, said second thermostatic means being arranged to energize said heating means and said .inert gas circulating means in response to a demand for refrigeration by said second evaporator, and manually operable means for adjusting the control pointof said first thermostatic means.

12. In an absorption refrigerating mechanism, a source of refrigerant liquid including a heated part, means for heating said heated part, a first evaporator, a second evaporator, an inert gas circulating means, flow directing means for directing the flow of inert gas from said circulating means to a selected evaporator, flow directing means for directing refrigerant liquid from said ,source, of refrigerant liquid to said selected evaporator, a first thermostatic means responsive to a" thermal condition produced by said first evaporator, a second thermostatic means responsive to a thermal condition produced by said second evaporator, said first thermostatic means being arranged to condition said flow directing means for operation under the control of said second thermostatic means to direct refrigerant liquid and inert gas into said second evaporator when there is no demand for refrigeration bysaid first evaporator and to condition said flow directing'means to supply refrigerant liquid'and inert gas to said first evaporator and to energize said heating means and said circulating means to produce refrigeration in said first evaporator in response'to a demand therefor, said second thermostatic means being arranged to energize said heating means and said inert gas circulating means in response to a demand for refrigeration by said second evaporator, and means for operating said first thermostatic means to condition normally evidencing lack of refrigeration demand by said first evaporator independently of the condition of said first evaporator.

13. 'Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including said absorber and a pair of evaporators, means for liquefying refrigerant vapor produced in said means connecting said evaporators in parallel with each other and in series with said absorber for circulation of inert gas therebetween, means for liquefying refrigerant vapor, means connecting said evaporators to said liquefying means in parallel, valve means in each of said connecting means arranged to direct the liquid refrigerant and inert gas into a selected one of said evaporators, and means arranged exteriorly of the fluid confining wall of said apparatus for producing operative magnetic fields for simultaneously operating each of said valve means.

15. In a refrigerator, a cabinetstructure including a pair of insulated refrigerating chambers; an absorption refrigerating apparatus associated with said cabinet structure including an evaporator in each of said chambers, an absorber positioned externally of said chambers, means providing for circulation of an inert gas between said evaporators and said absorber, a generator, means providing for circulation of absorption solution between said absorber and said generator, a condenser arranged externally of said chambers and connected to receive refrigerant vapor from said generator, and means for directin liquid refrigerant formed in said condenser and inert gas from said absorber into a selected one of said evaporators.

, 16. In a refrigerating apparatus of the absorp- 3 tion type a pair of evaporators, an absorber, means connecting said evaporators in parallel witheach other and in series with said absorber for circulation of inert gas therebetween, means for liquefying refrigerant vapor, means connecting said evaporators to said liquefying means in parallel, means in said connecting means for diciated with said cabinet structure including an evaporator in each of said chambers, an absorber positioned externally of said chambers, means providing for circulation of an inert gas between said evaporators and said absorber including means arranged to prevent flow of inert gas through a selected one of said evaporators, a generator, means providing for circulation of absorption solution between said absorber and said generator, a condenser arranged externally of said chambers and connected to receive refrigerant vapor from said generator, and means for directing refrigerant liquid from said condenser into the other of said evaporators.

18. In a refrigerating apparatus of the absorption type a pair of evaporators, an absorber, means connecting said evaporators in parallel with each other and in series with said absorber for circulation of inert gas therebetween, means for liquefying refrigerant vapor,- means connecting said evaporators to said liquefying means in parallel, valve means in each of said connecting means arranged to direct the liquid refrigerant and inert gas into a selected one of said evaporators, and magnetic means positioned exteriorly of the fluid confinin walls of said apparatus for simultaneously operating each of said valve 'means, and refrigeration demand responsive means controlling said magnetic means.

19. In a refrigerator; a cabinet structure including a pair of insulated refrigerating chambers; an absorption refrigerating apparatus associated with said-cabinet structure including an evaporator in each of said chambers; an absorber positioned externally of said chambers, means providing for circulation of an inert gas between said evaporators and said absorber including flow control means arranged to restrict the flow of inert gas to a selected one of said evaporators, a generator, means providing for circulation of absorption solution between said absorber and said generator, a condenser arranged externally of said chambers and connected to receive refrigerant vapor from said generator, means arranged to convey refrigerant liquid from said condenser to said selected one of said evaporators, and refrigeration demand responsive means for controlling the operation of said flow control means.

20. Absorption refrigerating apparatus comprising a plurality of vessels; means connecting said vessels to form a plurality of paths of flow of fluid including a path of flow of refrigerant fluid, a path of flow of absorption fluid and a path 'of flow of inert fluid; said vessels and said connecting means being hermetically sealed; fluid flow control valve means hermetically sealed in one of said paths of fluid flow; and magnetic means positioned outside said fluid flow path and operable to actuate said valve means by the magnetic field thereof passing through the fluid confining Walls of said path of fluid flow.

21. Absorption refrigerating apparatus comprising a circuit for absorption fluid including a generator and an absorber; a circuit for an inert pressure equalizing fluid including said absorber and an evaporator; a circuit for refrigerantfluid including said generator, said evaporator and' said absorber; fluid flowregulating valve means in one of said circuits; and magnetic field producing means positioned exteriorly of the fluid confining walls of the apparatus and arranged to operate said valve means by producing a magnetic fieldpassing through the fluid confining walls of the apparatus.

OTIS B. SUTTON. 

